Disarmament Diplomacy

New Nuclear Test Detectors

"Scientists at the Department of Energy's Pacific Northwest
National Laboratory in Richland, WA, have developed two
breakthrough devices that can detect nuclear detonations by
analyzing the atmosphere for traces of radioactive material. These
systems, once activated, will be located around the globe and used
to monitor the Comprehensive Nuclear-Test-Ban Treaty (CTBT) by
detecting nuclear explosions.

President Clinton has determined that non-proliferation of
nuclear weapons is one of the nation's highest priorities. The
Department of Energy is responsible for the United States' research
and development to monitor nuclear explosions in the context of a
test ban treaty. The Energy Department provides technological and
analytical support to guard against the spread of nuclear weapons
and weapons-usable materials and has long been actively involved in
preventing proliferation of nuclear weapons technology and
protecting nuclear material and facilities.

'These new technologies enhance the ability of the United States
and the international community to detect and confirm nuclear
explosions,' said Under Secretary of Energy Ernest Moniz. 'This
advancement in our ability to verify nuclear tests creates more
impetus for Senate debate and vote to ratify the Comprehensive
Nuclear-Test-Ban Treaty.'

ARSA / RASA

The two new detonation identification devices represent a
quantum leap beyond existing monitoring devices, with greater
sensitivity, full automation, near real-time reporting, and novel
nuclear radiation detectors. ARSA, the Automated Radioxenon
Sampler/Analyzer, and RASA, the Radionuclide Aerosol
Sampler/Analyzer, were created to verify the Comprehensive
Nuclear-Test-Ban-Treaty. An international monitoring system is
being set up to use the latest technology to watch for evidence
that nuclear weapons are being tested. ARSA and RASA will comprise
a large part of the technology employed in an 80-station
radionuclide network.

'ARSA is the most valuable radionuclide detection method
available to the CTBT,' said Ted Bowyer, Pacific Northwest
principal investigator for ARSA. 'These two systems allow us to
capture a tiny part of the weapon. Radionuclides are a smoking gun.
They are positive confirmation of recent nuclear fission.'

ARSA analyzes air samples for radioactive xenon, or radioxenon,
that seeps from underground nuclear explosions - the most common
testing method today but the most difficult to detect. ARSA has a
detection sensitivity 10 to 100 times greater than other systems
being used. In addition, it is the only completely automated
radioactive xenon monitor.

ARSA collects air samples, then processes them to trap the
radioactive xenon on cold charcoal. The system purifies the
radioactive xenon, then transfers it to a nuclear counting system.
The different isotopes of xenon are automatically measured, then
the results are automatically passed to a data center by
communication link. ARSA can be accessed by modem and programmed
remotely.

RASA detects fission products from atmospheric nuclear
explosions. This basic technique has been available for 30 years,
but Pacific Northwest researchers have created the most sensitive
automated system ever - more than 100 times as sensitive as the
best previous technology.

RASA filters a huge volume of air each day to check for evidence
of fission products from a nuclear explosion that attach to dust
particles. The automated system draws air through a series of
filters, which remove practically all of the atmospheric particles.
The filters are sealed, bar coded, then passed to a radiation
detection system. Radiation from weapons debris is then registered
and translated to prove a violation of the treaty. Information
collected by ARSA, RASA and other monitoring systems at the global
stations will be passed on to an international data center - a
prototype is currently located in Arlington, VA, and planned for
permanent housing in Vienna, Austria as part of the Comprehensive
Nuclear-Test-Ban Treaty's international monitoring system. The
other systems under development or in use include seismic,
infrasound and hydroacoustic monitors.

Development of both RASA and ARSA is sponsored by the Energy
Department's Office of Non-Proliferation and National Security with
the goal of transferring the technology to commercial vendors so
that any country can acquire the systems to meet its obligations
under the CTBT. Pacific Northwest is one of the Department of
Energy's nine multiprogram national laboratories and conducts
research in the fields of environment, energy, health sciences and
national security. Battelle, based in Columbus, OH, has operated
Pacific Northwest for DOE since 1965."